Injector



P. L. SCOTT Feb. 20, 1934.

INJECTOR 3 Sheets-Shet 1 Original Filed June 16, 1926 P. L. SCOTT Feb. 20, 1934.

I'NJECTOR Original Filed June 16. 1925 3 Sheets-Sheet 2 P r v ll q o F Q in. G. w

P. L. SCOTT Feb. 20, 1934. I

INJECTOR Original Filed June 16; 1926 3 Sheets-Sheet 3 w I w fiv'ezzfo z. I QPaZz' Z 50056.

Patented Feb. 20, 1934 UNlTED STATES PATENT OFFICE INJECTOR Philip Lane Scott, Chicago, 111., assignor to Super Diesel Tractor Corporation, La. Porte, Ind., a

corporation of New York 19 Claims. (Cl. roa

This invention relates to means for delivering liquid under high pressure and, if desired, intermittently at very high frequency and particularly for doing so without the use of mechanical drives and especially without the use of heavily loaded drives. While the invention has many applications, it is illustrated here in a general form adapted for use in connection with internal combustion engines of the injection type. By this is meant engines of the Diesel and the modifled Diesel cycle in which the fuel is injected into the engine. This case is a division of copending application 116,272, filed June 16, 1926, patented July 28, 1931, #1,816,157.

One object of the invention is to provide means for delivering liquid under very high pressure, intermittently at high frequency without any metal to metal driving contact at the delivery end. Another object is to provide means for delivering such liquid to the separate cylinders of an engine while using a single main pressure creating unit irrespective of the number of cylinders. Another object is to provide an apparatus of the type above suggested in which a single main pressure creating unit may be used to operate a plurality of final injection units which may be located at a considerable distance from such main unit. Other objects will appear from time to time throughout the specification and claims. Another object is to provide a structure adaptable to a variety of forms by which very high pressures may be applied to the fuel without excessive pressures occurring in the driving mechanism.

The invention is illustrated more or less diagrammatically in the accompanying drawings in which:

' Figure 1 is a vertical section of the combined pump of the complete hydraulic drive and fuel 0 injector;

Figure 2 is a plan view of the hydraulic motorinjector assembly;

Figure 3 is a vertical cross-section at line 3-3 of Figure-1 showing the details of the mechanical J return of themotor piston; v

Figure 4 is a section detail of a spring return of the motor piston.

A is a bed upon which the parts of the device as shown in the figures are mounted. The main retaining nut B erably be driven by such engine. B is a cross head provided with an upward depression B within which the enlarged head B of a pump plunger B is located. It is held therein by a The shaft B is provided with an eccentric 13 about which a collar B is mounted. The collar is joined by means of a connecting rod B to a wrist pin B positioned in the cross head 3*. p

C is an intake or suction passage within which is mounted a suction valve C normally held seated by a spring C C is a discharge passage within which the discharge or outlet valve C is seated and normally held on its seat by a spring C It communicates with a chamber C from which an outlet connection 0' leads to a high pressure pipe or conduit C. C is a low pressure or return pipe or conduit which communicates with the intake passage C. Thus, the

screw D When for any reason severe pressure is developed in the chamber C the valve D is operated and fluid is thereby-permitted to pass through the pipe D and from the high pressure side of the pump, back to the low pressure side.

In the form shown in Figures 1, 2 and 3, the injector units are four in number. They are all grouped together in a single housing E. Rotated within this housing are two tubular distributor rotors located in a cylindrical bore formed in the housing E. E is the high pressure rotor and the conduit C communicates with it through a suitable fltting and supplies it with the Iiquidunder pressure. E is a corresponding low pressure rotor and it discharges'into the conduit C Each of the rotors is provided with four openings or perforations spaced progressively about the'rotor 90 apart. The rotor E is provided with the several perforations or ports E and the rotor E is provided with the perforations or ports E One of the ports in each rotor is effective for one injector unit which acts upon one engine cylinder. A description of one such. unit will suffice for all. The housing E is provided with one or more central bores F, each of which has a reduced portion F Lying within the central bore F is ill a motor plunger H having an extension thereon H operating in the reduced bore F Between the reduced plunger H and the motor plunger H is a slotted section H adapted to carry in the slot K the rounded end K of a rocker arm K F is a lateral bore opening into the main bore F. F is connected by vertical passages with a pair of rotary valves E E which valves are ported at E E and mounted to be driven with the ports approximately 180 out of phase to control the admission and discharge of liquid vto and from the lower portion of the cavity F underneath the motor plunger H. H is a slot or'aperture in the body E sufiicient to clear the rocker K in its extreme positions.

J J are bracket arms pivoted concentrically with the shaft E These bracket. arms are joined by a longitudinal member J and they are thus held in the same position and may be moved together. J is a bracket fastened to the housing E and located generally centrally of the longitudinal member J J is a stud projecting from the bracket upon which is mounted for rotation a cam J which is joined to an arm J by means of which it may be moved. The cam J bears against the longitudinal member J and as it is rotated, moves the member rotating it and the ,bracket arms J about a point concentric with the shaft E".

K is a cam shaft pivoted on the arms J J and carrying four cams K spaced, in the form shown, apart. This arrangement may be varied for different types of engines or uses of the ap'paratus. The rocker arm K already described as having a bearing in the plunger H, has at the opposite end a nose K upon which the cam K may operate. As the cam K rotates it raisesone end of the rocker K and depresses the other, tliereby driving the piston H. The rotary valves E E are driven in phase with each other by the gears E E which in turn are driven by the gear B mounted on the shaft B Consequently if the shaft B is driven by the engine the rotary valves are in some desired timed relation with" the engine, and consequently the motor piston and pump plunger are timed by the engine. The

cams are timed by a secondary gear train comprising gears K' and E On the shaft K is a driven gear K". It is-in mesh with the driving gear E and driven by it.

Although I have shown an operative device, still it will be obvious that many changes might be made in size, shape and arrangement of parts without departing materially; from the spirit of my invention; and I wish, therefore, that my showing be taken as in sense diagrammatic.

J is a helical spring mounted about the stud- J and bearing against a washer J and a nutJ on said stud. The spring thus bears against the top of the cam'hub-J and holds it against accidental movement.

X is a tension spring fastened at X to the arm J and fastened to the projection X fixed on the housing E. The tension of the springs tends to rotate the cam shaft and frame which carries it downwardly and to hold it against the cam J to prevent accidental movement away from .its ad.- justed position. 1

The use and operation of my invention is as follows:

The mechanism including the pump barrel B plunger B", its associated drive and the intake valve 0 the discharge valve 0 the accumulator C and the relief valve D forms a power supply by delivering a relatively steady flow of a driving liquid, which preferably is a viscous oil, making it possible to use relatively large tolerances in the construction of the apparatus requiring in general simple pipe fittings and joints. This driving liquid power supply may be run at any desired speed driven from the crank shaft of an engine for example. In turn it may drive the motor injector units by any suitable gear train B B7, which may have any desired ratio. The driving liquid is conducted from the accumulator chamber C where pressure fluctuations are.

damped out to the motor injector unit proper, shown in detail in Figure 3. This driving liquid is conducted into a hollow rotary sleeve valve B which lies within the main body unit E. As this rotary valve turns the series ports shown as E in Figures 1 and 3 open in sequence into the series of channels F permitting driving liquid to enter and act upon the lower side of the motor pistons H, forcing these pistons upward and causing a power stroke of the connected high pressure pump plunger H This high pressure pump plunger extends into a conventional pumping chamber with intake and suction valves, inlet connections from a fuel supply and outlet connections to delivery points, such as fuel atomizers not shown in detail since they form no essential part of the invention. During the period in which the ports E register with the respective channels F", the outlet from the channel F and the cavity below the motor piston is blocked by a second rotary valve E driven'in phase with the first valve through the gear train E E At some desired time after the completion of the power stroke of each motor piston the cam mechanism, comprising the gear K", shaft K and cams K will act in proper sequence upon the series of rockers K These rockers pivoted at K will in turn depress the motor plungers at proper intervals causing the return .motion of the mechanism and consequently the suction stroke of the high pressure pump plunger H During this phase the ports E in the second rotary valve E come successively into register with the channels F permitting the spent driving liquid to escape from beneath the motor pistons as the pistons are returned and pass into the return pipe 0*,

and from thence back into the driving liquid power pump. The purpose of the mounting of the rotatable cam shaft mounting, comprising the brackets J J, bar 'J and the adjusting cam J with its control handle J is to vary the length of the return stroke of the motor piston by varying the available rise of the cams K acting upon the respective rockers K For example, for full *delivery capacity the cam shaft and cams are raised to a point of maximum effective lift which in turn produces the longest return stroke of the motor piston. It is evident that, the piston being returned, the driving liquid is able to force it back on a power stroke to the full length. of the initial return motion. For reduced delivery capacity the cams are moved downward away from therockers and the rockers consequently return the pistons for a portion of the possible stroke which in turn limits the succeeding power stroke to that amount. Since the whole cam mechanism is journaled about the axis of the driving gear, the cams function equally well throughout this movement.

It will be seen that this system avoids the serious difficulty of a mechanical drive capable of developing several thousand pounds pressure directly upon a relatively non-viscous oil, particularly at high speeds, say from 1000 R. P. M.

upward, since a liquid is used as the driving medium and this liquid may'be chosen solely for the purpose of transmitting power in an inexpensive and simple hydraulic system. By the use of a differential plunger the relatively low pressures required in the driving liquid are multiplied several times upon the fuel, making it possible with reasonable design proportions to attain a pressure of l0,000#/sq. in. upon the fuel withfr'om one to two thousand pounds in the driving liquid circuit. A mechanical linkage to return the plungers on their suction strokes has been used in this system since the objections to mechanical motion are much less serious in this case, due to the fact that a much longer time is available for return than for injection. In general, some six to ten times as much time; further, the return stroke may commence gradually whereas the injection stroke must commence sharply, and lastly, the return stroke will operate against comparatively little resistance, merely that necessary to overcome inertia and force liquid through relatively large passages. The problem of developing several thousand pounds per square inch pressure upon the fuel is absent. The use of the mechanical drive permits a substantial advantageous reduction in the size and complexity of the hydraulic drive.

I claim:

1. In a multiple high pressure fuel pump for internal combustion engines, a plurality of pump barrels, high pressure plungers arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality of hydraulic motor pistons connected to said plungers, a plurality of plunger barrels housing said motor plungers, valve means for admitting and discharging low pressure driving liquid to and from said barrels to cause said plungers to perform power strokes in predetermined timed relation, and mechanical means associated with each motor plunger adapted to return said motor plungers in predetermined timed phase succeeding each power stroke.

2. In a multiple high pressure fuel pump for internal combustion engines, a plurality of pump barrels, high pressure plungers arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality of hydraulic motor pistons connected to said plungers, a plurality of plunger barrels housing said motor plungers, unitary valve means for admitting and discharging low pressure drivingliquid to and from said barrels to cause said plungers to perform power strokes in predetermined timed relation, and mechanical means associated with each motor plunger adapted 'to return said motor plungers in predetermined timed phase succeeding each power stroke.

3. In a multiple high pressure fuel pump for internal combustion engines, a plurality of pump barrels, high pressure plungers arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality of hydraulic motor pistons connected to said plungers, a plurality of plunger barrels housing said motor plungers, valve means for admitting and discharging low pressure viscous driving liquid to" and from said barrels to cause said plungers to perform power strokes in predetermined timed relation, and mechanical means associated with each motor plunger adapted to return said motor plungers in predetermined timed phase succeeding each power stroke.

4. In a multiple high pressure fuel pump for internal'combustion engines, a plurality of pump barrels, high pressure plungers arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality of hydraulic motor pistons connected to said plungers, a plurality of plunger barrels housing said motor plungers, valve means for admitting andv lation, and positive mechanical means associated with each motor plunger adapted to return said motor plungers in predetermined timed phase succeeding each power stroke.

5. In a multiple high pressure fuel pump for internal combustion engines, a plurality of pump barrels, high pressure plungers arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality of hydraulic motor pistons connected to said plungers, a plurality of plunger barrels housing said motor plungers, valve means for admitting and discharging low pressure driving liquid to and from said barrels to cause said plungers to perform power strokes in predetermined timed relation, and positive non-yielding mechanical means associated with'each motor plunger adapted to return said mo'tor plungers in predetermined timed phase succeeding each power stroke.

6. In a multiple high pressure fuel pump for internal combustion engines, a plurality of pump barrels, high pressure plungers arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality vof hydraulic motor pistons directly connected to said plungers, a plurality of plunger barrels housing said motor plungers, valve means for admitting and discharging low pressure driving liquid to and from said barrels to cause said plungers to perform power strokes in predetermined timed relation, and mechanical means associated with each motor plunger adapted to return said motor plunger in predetermined timed phase succeeding each power stroke.

'7. In a multiple high pressure fuel pump for internal combustion engines, a plurality of pump barrels, high pressure plungers adapted to pump relatively non-viscous liquid arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality of hydraulic motor pistons directly connected to said plungers, a plurality of plunger barrels housing said motor plungers, valve means for admitting and discharging low pressure viscous driving liquid to and from said barrels to cause said plungers to perform power strokes in predetermined timed,

relatively nonviscous liquid arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality of hyrdaulic motor pistons connected to said plungers, a plurality of plunger barrels housing said motor plungers, unitary valve means for admitting and discharging low pressure viscous driving liquid to and from said barrels to cause said plungers toperform power strokes in predetermined timed relation, and mechanical means associated with each motor plunger adapted to return said motor plungers in predetermined timed phase succeeddriving liquid to and from said barrels to cause said plungers to perform power strokes in predetermined timed relation; and positive mechanical means associated with each motor plunger adapted to return said motor plungers in predetermined timed phase succeeding each power stroke.

10. In a multiple high pressure fuel pump for internal combustion engines, a plurality of pump barrels, high pressure plungers arranged to reciprocate in said barrels, intake and discharge valves associated therewith, a plurality of hydraulic motor pistons directly connected to said plungers, a plurality of plunger barrels housing said motor plungers, unitary valve means for admitting and discharging low pressure viscous driving liquid to and from said barrels to cause said plungers to perform power strokes in predetermined timed relation, and positive non-yielding mechanical means associated with each motor plunger adapted to return said motor plungers in predetermined timed phase succeeding each power stroke.

11; In a high pressure multiple fuel pump for internal combustion engines and the like, a housing containing a series of high pressure pump cylinders and an associated series of single acting hydraulic motor cylinders, inlet and outlet valves arranged to control flow of liquid fuel to and from the high pressure cylinders, high pressure plungers positioned to operate in said high pressure cylinders, low pressure motor pistons positioned to operate in said hydraulic motor cylinders and connected to said high pressure plungers, valve means adapted to control flow of driving liquid to and from said motor cylinders to cause power strokes in predetermined timed relation of said motor pistons and'to permit discharge of spent driving liquid from said motor cylinders, a series of mechanical linkages adapted to return the respective motor pistons after each power stroke, and means for supplying a steady flow of driving liquid to said motors.

12. In a high pressure multiple fuel pump for internal combustion engines and the like, a housing containing a series of high pressure pump cylinders and an associated series of single acting hydraulic motor cylinders, inlet and outlet valves arranged to control flow of liquid fuel to and from the high pressure cylinders, high pressure plungers positioned to operate in said high pressure cylinders, low pressure motor pistons positioned to operate in said hydraulic motor cylinders and directly connected to said high pressure plungers, valve means adapted to control flow of driving liquid to and from said motor cylinders to cause power strokes in predetermined timed relation of said motor pistons and to permit discharge of spent driving liquid from said motor cylinders, a series of mechanical linkages adapted to return the respective motor pistons after each power stroke, and means for supplying a steady flow of driving liquid to said motors.

13. In a high pressure multiple fuel pump for internal combustion engines and the like,-a housingcontaining a series of high pressure pump cylinders and an associated series of single acting hydraulic motor cylinders, inlet and outlet valves arranged to control flow of liquid fuel to and from the high pressure cylinders, high pressure plungers positioned to operate in said high pressure cylinders, low pressure motor pistons positioned to operate in said hydraulic motor cylinders and connected to said high pressure plungers, unitary valve means adapted to control flow of driving liquid to and from said motor cylinders to cause power strokes in predetermined timed relation of said motor pistons and to permit discharge of spent driving liquid from said motor cylinders, a series of mechanical linkages adapted to return the respective motor pistons after each power stroke, and means for supplying a steady flow of driving liquid to said motors.

14. In-a high pressure multiple fuel pump for internal combustion engines and the like, a housing containing a series of high pressure pump cylinders and an associated series of single acting hydraulic motor cylinders, inlet and outlet valves arranged to control flow of liquid fuel to and from the high pressure cylinders, high pressure plungers positioned to operate in said high pressure cylinders, low pressure motor pistons positioned to operate in said hydraulic motor cylin-r ders and connected to said high pressure plungers, valve means adapted to control flow of driving liquid to and from said motor cylinders to cause power strokes in predetermined timed relation of said motor pistons and to permit discharge of spent driving liquid from said motor cylinders, a series of positive mechanical linkages adapted to return the respective motor pistons after each power stroke, and means for supplying a steady flow of driving liquid to said) motors.

15. In a high pressure multiple fuel pump for combustion engines and the like, a housing containing a series of high pressure pump cylinders and an associated series of single acting hydraulic motor cylinders, inlet and outlet valves arranged to control flow of relatively non-viscous liquid fuel to and from the high pressure cylinders, high pressure plungers positioned to operate in said high pressure cylinders, low pressure m0- tor pistons positioned to operate in said hydraulic motor cylinders and connected to said high pressure plungers, valve means adapted to control flow of relatively viscous driving liquid to and from said motor cylinders to cause power strokes in predetermined timed relation of said motor pistons and to permit discharge of spent driving liquid from said motor cylinders, a series of mechanical linkages adapted to return the respective motor pistons after each power stroke, and means for supplying a steady flow of driving liquid to said motors.

16. In a high pressure multiple fuel pump for internal combustion engines and the like, a housing containing a series of high pressure pump cylinders and an associated series of single acting hydraulic motor cylinders, inlet and outlet valves arranged to control flow of relatively non-viscous liquid fuel to and from the high pressure cylinders, high pressure plungers positioned to operate in said high pressure cylinders, low pressure motor pistons positioned to operate in said hydraulic motor cylinders and connected to said high pressure plungers, unitary valve means adapted to control flow of relatively viscous driving liquid to and from said motor cylinders to cause powerstrokes in predetermined timed relation of said motor pistons and to permit discharge of spent driving liquid from said motor cylinders, a series of mechanical linkages adapted to return the respective motor pistons after each power stroke, and means for supplying a steady flow of driving liquid to said motors.

17. In a high pressure multiple fuel pump for internal combustion engines and the like, a housing containing a series of high pressure pump cylinders and an associated series of single acting hydraulic motor cylinders, inlet and "outlet valves arranged to control flow of relatively nonviscous liquid fuel to and from the high pressure cylinders, high pressure plungers positioned to operate in said high pressure cylinders, low pressure motor pistons positioned to operate in said hydraulic motor cylinders and directly connected to said high pressure plungers, unitary valve means adapted to control flow of relatively viscous driving liquid to and from said motor cylinders to cause power strokes in predetermined timed relation of said motor pistons and to permit discharge of spent driving liquid from said motor cylinders, a series of positive mechanical linkages adapted to return the respective motor pistons after each power stroke, and means for sure cylinders, highpressure plungers positioned to operate in said high pressure cylinders, low pressure motor pistons positioned to operate in said hydraulic motor cylinders and directly connected to said high pressure plungers, unitary valve means adapted to control flow of relativel viscous driving liquid to and from said motor cylinders to cause power strokes in predetermined timed relation of said motor pistons and to permit discharge of spent driving liquid from said motor cylinders,. resilient means adapted to return the respective motor pistons after each power stroke,'and means for supplying a steady flow of driving liquid to said motors.

19. In a high pressure multiple fuel pump for internal combustion engines and the like, a series of high pressure pump cylinders and an associated series of single acting hydraulic motor cylinders, inlet and outlet valves arranged to control flow of liquid fuel to and from the high pressure cylinders, high pressure plungers positioned to operate in said high pressure cylinders, low pressure motor pistons positioned to operate in said hydraulic motor cylinders and connected to said high pressure plungers, valve means adapted to control flow of driving liquid to and from said motor cylinders to cause power strokes in predetermined timed relation of said motor pistons and to permit discharge of spent driving liquid from said motor cylinders, a series of mechanical linkages adapted to return the respective motor pistons after each power stroke, and means for supplying a steady flow of driving liquid to said motors.

' PHILIP LANE SCOTT. 

